Why do women who spend time together, start getting their period at the same time?

Question

Serin- your response does not surprise me. I've read some of your other comments, about how women are inferior etc. so I am not interested in what you have to say.

Thank you FANNY- I agree with you.

Answer 1

Maybe it's the "sisterhood" connection.
We women can be alot more sympatico with each other, mentally, physically, emotionally, then men.

Maybe it's Elohim's way of allowing us to be miserable and happy and free at the same time to be understanding with each other in the work place.

I believe the first manifestation of God-Creator was a Female spiritual enity.

Answer 2

That's actually an urban legend. Check out the website in the source for an entertaining and insightful treatment of the subject:

" * Apparent clustering of menstrual onsets doesn't necessarily mean anything. Assuming an average cycle of 28 days, the maximum time between two women's onsets is 14 days. Since the minimum is zero, the average difference--what you'd expect purely by chance--is seven days, and half the time would be less. (In 1971 McClintock said she'd observed a decline in the average difference from seven days to five.) What's more, women recording their onsets after the fact often misremember or are influenced by the recollections of their friends, skewing the data.

* Menstrual synchrony in any meaningful sense is impossible when the women have cycles of different lengths. (Cycle length varies considerably among women not using the pill.) Though a woman with a 27-day cycle might initially have her onset on the same day as a woman with a 29-day cycle, the next month she'd be two days earlier, the month after that four days, and so on. No one has shown that supposedly synchronized women have cycles of the same length--or that their cycles, if of different lengths at first, diverge less than they should over time.

* Methodological errors can easily bias a data set to show menstrual synchrony where none exists. To demonstrate one common problem: Suppose a study starts on October 1. Subject A, with a 28-day cycle, has an onset on September 27, another on October 25, and a third on November 22. Subject B, with a 30-day cycle, has an onset on October 5 and another on November 4. A naive investigator could report that these subjects were 20 days apart at the outset (October 25 vs October 5) and 18 days apart at their second onset (November 4 vs November 22). Ergo, the two are synchronizing. In fact, the two subjects were eight days apart to start with (September 27 vs October 5) and are diverging. Of course you can set up the numbers to arrive at the opposite conclusion; the point is that given the small samples commonly used in studies of menstrual synchrony, it's easy to lead oneself astray. One skeptic (H.C. Wilson, 1992) has claimed that when you correct all the errors, including McClintock's, the evidence for menstrual synchrony evaporates."

Answer 3

It is not a proven theory as there is no physiological explanation yet, but the primary idea is that the women pick up each others' pheromones. The pheromones can increase the production of Luteinizing Hormone in women. Luteinizing Hormone is naturally released by our pituitary glands and are what trigger our ovulation phase to start.

Answer 4

The short answer is pheromones, odorless chemicals secreted by the body which can affect other people. Menstruating women secrete certain ones which are somehow perceived by women they have frequent close contact with. They then tend to cycle closer together.

Answer 5

I think it has something to do with pheromons and group dynamics.(This usually happens in female jail modules or prisons or even some work settings.) Since in ye olde cave man days it would be safer to have children in a group. Sort of like a human fail safe.

Answer 6

One theory, and I'm being serious here, is that women's bodies secrete pheremones so that they're cycles will all slowly alter until they are the same. The proposed reason for this is so men don't have to deal with them during their menstruation throughout the whole month. Imagine a group of men and women...the second one woman finished, another would follow...it would never end. I'm serious, I read that as a theory...just thought it should be put up on here.